Packaging Guides
How to Measure Poly Bags Correctly
Choosing the correct poly bag size is important for proper fit, product protection, and packaging efficiency. This guide explains how to measure layflat bags, gusseted bags, pallet covers, gaylord liners, and reclosable bags using simple formulas and examples.
Measuring Guide
Layflat Bags – Square Container or Dimensional Product
Note: Depth is the shorter of the two sides.
- Bag Width = Container Width + Container Depth + 2" for a looser fit.
- Bag Length = Container Height + Container Depth + 6" to cover contents and tie the bag closed.
Examples
Container Size: 14" W x 10" D x 32" H
Bag Size: 26" W x 48" L
Object Size: 10" W x 3" D x 16" H
Bag Size: 15" W x 25" L
Measuring Guide
Layflat Bags - Round Container
- Container Circumference = Diameter x 3.14
- Bag Width = Container Circumference ÷ 2 + 1" for a looser fit.
- Bag Length = Container Height + Container Diameter + 6" for overhang.
Example
Container Size: 12" D x 30" H
Bag Size: 20" W x 47" L
Measuring Guide
Reclosable Bags
Note: Domestically produced custom reclosables come with reinforced hammerseals; standard stock reclosables and imported custom reclosables do not.
- Bag Width = Width of Product + 1½"
- For rigid items, add ½" more to the bag width to allow the item to fit.
- Bag Length = Length of Product + 1"
- For thick or bulky items, add the product depth to both width and length.
- Add ½" to 2" to both dimensions for a looser fit.
Example
Flat Product: 2½" W x 5½" H
Bag Size: at least 4" W x 6" L
Measuring Guide
Slider Top Bags
- Bag Width = Width of Product + 1½"
- For rigid items, add ½" more to the bag width to allow the item to fit.
- Bag Length = Length of Product + ½"
- For thick or bulky items, add the product depth to both width and length.
- Add ½" to 2" to both dimensions for a looser fit.
Example
Flat Product: 2½" W x 5" H
Bag Size: at least 4" W x 6" L
Measuring Guide
Gusseted Bag – Pallet Cover
Width = wider side • Depth = shorter side • Height = height of block or container
- Cover Width = Pallet Width + 2"
- Cover Depth = Pallet Depth + 2"
- Cover Length = Pallet Height + ½ Pallet Depth
Example
Pallet Size: 40" W x 36" D x 50" H
Cover Size: 42" W x 38" D x 68" L
Measuring Guide
Gusseted Bag – Gaylord Liner
Width = wider side • Depth = shorter side • Height = height of block or container
- Bag Width = Box Width + 1"
- Bag Depth = Box Depth + 1"
- Bag Length = Box Height + Box Depth + 6" to cover contents and tie the bag closed.
Example
Box Size: 18" W x 12" D x 14" H
Bag Size: 19" W x 13" D x 32" L
Frequently Asked Questions
How do I measure a poly bag correctly?
Start with the product or container dimensions, then add the appropriate allowance based on bag style, product depth, and desired fit.
What is the difference between bag width and bag length?
Bag width measures side-to-side across the opening. Bag length measures from the bottom of the bag to the open end or usable length depending on bag style.
Should I size up for bulky or rigid products?
Yes. Rigid or thick products often require extra width and length to allow proper insertion and a more comfortable fit.
Do gusseted bags measure differently than layflat bags?
Yes. Gusseted bags require width, depth, and height calculations, while layflat bags are typically measured using width and length with depth allowances added as needed.
Need help choosing the right bag size?
Contact Pioneer Poly Products for help selecting the right stock or custom poly bag, liner, tubing, or sheeting size for your application.